1. Field of the Invention
The present invention relates to an image compression data processing method and an image compression data processing apparatus that divide compressed image data into multiple pieces of compressed partial image data and are capable of describing the multiple pieces of compressed partial image data in an arbitrary order.
2. Description of the Related Art
When compressed image data is to be distributed from a sending side device (server) to a receiving side device (client), for example, sub-band encoding such as specified in JPEG2000 is first applied to the DCT blocks of the image data as disclosed in Patent Document 1. Here, DCT is an abbreviation for Discrete Cosine Transform and JPEG is an abbreviation for the Joint Photographic Experts Group.
Then, based on a specified order of reading relating to at least one of appearance definition (designation of region) or a spatial frequency band provided from the receiving side device, the sending side device reorders the data and distributes the reordered data. The receiving side device then decodes and displays or otherwise handles the data.
Patent Document 2 discloses a technique which uses JPEG2000 to determine a Region of Interest (ROI) in advance and to reorder compressed image data with priority being given to the ROI of an image hit in a keyword search or a search for an image feature amount (similar image retrieval), and then the compressed image data is distributed.
[Patent Document 1] Japanese Patent Application Laid-Open No. 5-290093
[Patent Document 2] Japanese Patent Application Laid-Open No. 2001-160062